ERN-LUNG is a network of European patients and healthcare providers dedicated to ensuring and promoting excellence in care and research to the benefit of patients affected by rare respiratory diseases. ERN-LUNG’s vision is to be a European knowledge hub for rare respiratory diseases and to decrease morbidity and mortality from rare respiratory diseases in people of all ages. ERN-LUNG is a European Reference Network (ERN), a non-profit, international, professional, patient centred network. ERN-LUNG is focused on rare respiratory diseases and is made up of nine core networks representing the diversity of diseases and conditions affecting the lungs. The current core networks (sub-thematic areas) are interstitial lung diseases, cystic fibrosis, pulmonary hypertension, primary ciliary dyskinesia, non-CF bronchiectasis, alpha1-antitrypsin deficiency, mesothelioma, chronic lung allograft dysfunction, and other rare lung diseases. In addition to the sub-thematic groups, ERN-LUNG is also organized in functional committees tackling horizontal topics, affecting all of the current and future core networks of ERN-LUNG. These functional committees are Research and Clinical Trials, Ethical Issues, Registries and Biobanks, Patient Recorded Outcomes and Quality of Life, Quality Management, Physical Fitness and Training, Social Services, Guidelines and Best Practice of Care, Communication and Outreach, Cross Border Care, and Professional Training and Continued Medical Education. In building up on and learning from mature networks of recognized international excellence, ERN-LUNG will continue to grow, to establish registries and clinical trial networks, and add value for patients, healthcare providers, and professionals through dissemination of knowledge, enhancement of general expertise by learning from the best centres in rare respiratory diseases in Europe, and improvement of standards of care, quality of life and prognosis for the whole spectrum of rare pulmonary diseases.